Because of multiple scattering, laser beam is diffused and transforms into speckle when propagating through scattering media, such as milk, biological tissue et al. Realization of diffused light into a focal spot by modulating the wavefront of the incident beams is of great significance. In this study, focusing laser beams through opaque scattering media is achieved by introducing the spatial light modulator and continuous sequential feedback algorithm to modulate phase of the incident beam. The maximum enhancement factor of intensity obtained is 50.6139. The influence of the number of square segments of the spatial light modulation and the phase precision of every segment on the enhancement factor of intensity is discussed. Experimental result shows that light intensity at the target area increases with the increasing number of square segments of the spatial light modulation, and becomes stronger with the increasing phase precision.